1. Field of the Invention
The present invention relates to an organic EL display panel, and in particular to technology for improving aperture ratio.
2. Description of the Related Art
In recent years, research and development has progressed in the area of organic electroluminescence (hereinafter “organic EL”) display panels that use the phenomenon of electroluminescence of organic material. Each organic EL cell composing an organic EL display panel is composed of an anode, a cathode, and an organic light-emitting layer provided therebetween. The anode is layered on an interlayer insulation film that is layered on a Thin Film Transistor (TFT) substrate for driving the cells. To connect the anode with an electrode of the TFT, a through-hole (contact hole) is provided in the direction of thickness of the interlayer insulation film. So that the contact hole will not emit light, the contact hole is buried under the bank. However, such a structure hinders improvement of aperture ratio, which prevents an increase in the light-emitting surface area in an organic EL display panel and prevents improvement of luminous efficiency (see Patent Literature 1).